The present invention pertains to a blade sharpening device and more particularly to a blade sharpening device equipped with a steel shaping section and a stone sharpening section and its use.
Knives such as those used by meat markets and meat processing plants are prone to become dull after frequent use. The knife blade edge will typically curl as well as becoming dull by its use. Butchers use an instrument referred to as xe2x80x9ca steelxe2x80x9d to uncurl a curled or bent knife edge. The steel is a hardened piece of tapered steel rod which the user deftly slides along the knife""s edge on each blade edge in brisk repetitive movements so as to uncurl the bent knife""s edge. The knife sharpener will then typically use a wet stone or a grind stone to sharpen the uncurled blade""s edge. This is also accomplished by skillfully and repetitively sliding the blade""s edge at about a 15 degree angle against the stone along the longitudinally axis of the knife""s edge on both edges until it is sharp. The xe2x80x9csteelxe2x80x9d and wet stone instruments have been used separately as separate tools for ages to uncurl and sharpen the edges of blades.
Numerous patents, both foreign and domestic, have been granted on various knife sharpening devices. Great Britain patent 869491 to Knupp discloses a knife sharpener equipped with two whet steels that intersect at an angle. In order to sharpen the knife blade is placed between the two whet steels and the sharpeners are moved longitudinally to and from along the blade edge until sharpened. In U.S. Pat. No. 3,819,170 to Longbrake, there is disclosed a portable hand-held sharpener with a clamping means. The device is composed of a stone file equipped with clamp means for holding in place any given object to be sharpened. To avoid potential injury to the user, the user makes contact with the object with a separate sharpening member. In another U.S. Pat. No. 4,170,343 to Longbrake, there is disclosed a portable knife sharpener apparatus for holding and maintaining an article during sharpening. The invention embodies two parts on of which is the hand-held clamping means (two clamp members) for holding the knife to be sharpened and a rectangular sharpening stone. In U.S. Pat. No. 4,512,112 to LeVine, there is disclosed knife sharpener clamp equipped with a guide member of the same width as the clamp member, openings to receive a guide rod of the sharpening stone hold, a guide rod of a sharpener stone holder which carries a sharpening stone, and receiving openings in the clamp to facilitate the user""s grasp. In U.S. Pat. No. 4,528,777 to Bernstein, et al, there is disclosed a knife sharpener device that has a grinding element which can be used on a knife edge in a spiral path through 180 degree traverse and reverse actions. The Bernstein, et al, patent includes a stationary mounting plate having a groove for receiving and retaining a blade to be sharpened, and an elongated knife blade positioned in the groove of a mounting plate, a U-shaped bracket pivotally mounted on one side of the plate beneath and to one side of the groove, and a means for maintaining constant contact between the grinding element and the edge of said knife. In U.S. Pat. No. 4,558,540 to Collins, there is disclosed a portable hand-held knife sharpener that has a telescoping sharpening element that is housed in a tray and which has a bolt-action button device for extending and retracting the sharpening element. The sharpening element or stone is composed of an aluminum composite. In U.S. Pat. No. 4,777,770 to LeVine, there is disclosed an elongated sharpening stone with a design for improved sharpening by use of a carefully spaced finger grip for protection wherein the user can slide the sharpener in a sweeping motion across the knife. In U.S. Pat. No. 5,163,251 to Lee, there is disclosed ahand-held knife sharpener wherein the user positions the blade to be sharpened between an area as depicted therein. The Lee patent design reportedly allows safe usage when the knife is being sharpened as it faces downward in relation to the user. U.S. Pat. No. 6,398,633 to Lothe discloses a hand held sharpener for sharpening the cutting edge of a blade of a cutting tool comprising a housing, a mounting surface, a sharpener with three stones mounted against the mounting surface to form the sharpener having a center stone, a left stone and a right stone.
There exists a need for a single tool which may be effectively utilized to both uncurl and sharpen a blade""s edge.
The present invention provides a blade edge uncurling steel (referred in the trade as a xe2x80x9csteelxe2x80x9d) and blade edge sharpening device.
The tool 1 includes a handle 3, an accessible stone retaining shaft 4 supportive of a removable sleeved stone sharpening section 5 attached to the handle 3 at one shaft end and connected to a coned-shaped steel shaping section 2 for uncurling a blade edge at an opposite end. The stone retaining shaft 4 supports a circumscribing hollow cylindrical sleeved stone section 5 snuggly nestled between the handle 3 and the steel shaping section 2. The stone retaining shaft 4 is designed so as to permit access to the sleeved stone sharpening section 5 and allow the stone to be removed and replaced with another sleeved stone section 5 when necessary. The steel retaining shaft 4 needs to be accessible for sleeve 5 replacement and this may be separable from either steel shaping section 2 or handle 3 so access may be readily obtained to the steel retaining shaft 4 and sleeved stone section 5. The uncurling and sharpening device 1 is especially adapted so as to permit the stone sharpening section 2 to be removed or replaced from the stone retaining shaft 4 mount. This may be effectively accomplished by allowing the accessibility to the stone retaining shaft 4 by separating it from the handle or from the steel section so as to provide open access to the stone sharpening section 5.